Coin controlled time switch



Jane 3938a H gTARK COM CONTROLLED TIME SWITCH Filed March 6, 1932 Invenbm: Julian Il. Stank,

h Patented Jan. 18, 19 38 PATENT OFFICE COIN CONTROLLED TIME SWITCH Julian H. Stark, Fort Wayne, Ind., assignor to General Electric Company, a corporation of New York Application March 8, 1932, Serlal No. 597,503

4 Claims.

My invention relates to coin or check controlled time switches, and its object is to provide a. switch of this character having few parts, and one which is simple, rugged, and entirely reliable in operation. In particular, my invention relates to an improvement in the time controlled mechanism for controlling the switch opening operations.

In carrying my invention into effect, I mainlo tain the load on the timing motor substantially constant when it is in operation and performing its timing function. The timing motor is caused to gradually store up energy in a spring and release the energy at the proper time to perform 1.) the resetting operation. All the energy for performing the resetting operation is thus supplied by the timing motor, but a heavy load is never imposed thereon, and, consequently, a small electric timing motor is able to perform this func- 20 tion with a high degree of timing accuracy and a small expenditure of energy.

The features of my invention which are believed to be novel and patentable will be pointed out in the claims appended hereto. For a better 25 understanding of the invention reference is made in the following description to the accompanying drawing showing an exploded perspective view of the various operating parts of a preferred embodiment of my invention and the circuit con- 30 nections associated therewith.

The coin controlled switch represented is arranged to accommodate a number of coins at one time. The coin chute is represented at I0, and when a coin of the proper value is inserted 35 in its top it drops upon a weighted lever I I which is thereby caused to turn on its pivot I2 and momentarily close resilient contacts represented at I3, releasing the coin and allowing the contacts to open again. Closure of contacts I3 by 4 the insertion of a coin in the chute momentarily energizes the coil of a credit relay I4 having an operating pawl I5. When this relay is energized its plunger and operating pawl I5 are caused to move upward, and they drop again as soon as the 45 coin clears the chute I0 and allows the contacts at I3 to open. Relay I4 operates a totalizing register I6 showing the total number of coins inserted. It also operates on a ratchet wheel I1, causing it to turn a definite fraction of a revolu- 50 tlon in a clockwise direction for each actuation. The upward movement of the relay plunger is limited by a stop I 8, and its pawl I5 is held in operating relation with ratchet wheel I1 in its upward movement by a light spring I9. Ratchet 55 wheel I! rotates a shaft on which are secured a credit disc 20, a switch-operating cam 2I, and spring fingers 22 comprising one member of a friction clutch. The credit disc 20 has twelve graduations and these graduations are numbered from 0 to, 11, respectively, and its purpose is to in- 5 dicate the number of coins that have been deposited for which service has not been rendered.

It will be understood that the mechanism will be contained in a suitable box and that the top of the coin chute will be accessible from the outside, 10 and that registers I6 and 20 will show through suitable windows in the box. The indication on disc 20 which will be exposed to view will be the one opposite the arrow shown at the bottom of the disc. A single depression 23 is contained in the periphery of the switch operating cam 2 I, and when the cam is in the no credit position, such that credit disc indicates zero, the depression 23 thereof is opposite a resilient switch operating arm 24, with the arm resting in the depression 90 and with the switch contacts 25 controlled by arm 24 in open position. In any other rotative position of cam 2| the position of arm 24 is changed to close switch contacts 25.

Cam disc 2| also contains a stop pin 26 which 25 cooperates with a stationary stop 21 which prevents rotation of the cam backwards beyond the zero position or forward beyond the I I coin credit position.

It will be noted that while there are 12 rota- 30 tive positions of disc 20 and the parts associated therewith, there are only 11 teeth in ratchet wheel I1. These teeth are spaced apart part of the circumference of the disc, and a tooth has been omitted at point 28. Thus, when relay I4 has advanced ratchet wheel I"! i-i of a revolution in a clockwise direction from the zero position shown, stop pin 26 will come to rest against stop 21 and point 28 of the ratchet wheel will be opposite pawl I5, so that even though the stop pin were omitted and additional coins were deposited, the relay will not advance the ratchet beyond this point, although the relay will be allowed to operate and register the deposit of the extra coins on the totalizing register I6. If the ratchet wheel were provided with a tooth opposite point 28, theplunger of the ratchet would be prevented from rising by reason of the blocking of the ratchet wheel at the stop and the register I6 would not be properly operated. The omission of the tooth at point 28 in the ratchet wheel and the operation resulting therefrom is a feature which is quite desirable in connection with some installment payment plans.

When switch contacts 25 are closed by rotation of cam 2| from a zero credit position, the service circuit from source 29 to some appliance 30 is closed. Also, the circuit to the timing motor indicated at 3| is closed through contacts 25. Consequently, energy is used by the timing motor only when its timing function is required. The appliance indicated at 30 may be an electric refrigerator, a radio receiving set, electric laundry apparatus, or some other electric device, payment for which or for its use is made by depositing coins in the coin switch.

The timing motor and associated parts are employed to return the switch cam 2| to a position to open the switch contacts 25 after a lapse of time, depending upon the number of coins inserted in the coin switch at a given time. The timing motor employed is preferably a small self-starting synchronous motor such as is commonly employed in electric clocks. 32 represents a speed reducing gear casing from which the terminal shaft 33 extends. Additional speed reducing worm gears 34 and 35 are provided as needed, such that gear 36 is rotated in a clockwise direction one revolution during the unit timing interval of the device. By unit timing interval I mean the length of time electric service may be rendered by the deposit of one coin. In the particular device here represented, the unit timing interval will be assumed to be 24 hours, and consequently the timing motor 3| when in operation rotates gear 35 at the rate of one revolution in 24 hours in a clockwise direction. Gear 36 is free to rotate on shaft 31 and is secured by a hub to the inner end of a spiral spring 33. This spring is enclosed in a spring barrel 39 and to which the outer end of the spring is secured. Barrel 39 together with gear pinion 40 and gear 4| are secured to shaft 31. Gear 4| meshes with a pinion 42 secured to a speed limiting device, such as a fan 43. Pinion 4D meshes with a large gear 44, which comprises the second member of the friction clutch previously referred to, the other member thereof comprising the resilient arms 22 which are rotated with the switch cam 2|. The shaft which supports disc 20, ratchet wheel I], and cam 2| extends through and supports gear 44, but the latter is free to turn on this shaft, except as resisted through the clutch coupling afforded by the friction of the spring fingers 22 on the face of the gear. A collar, not visible in the drawing, is secured to the shaft behind gear 44, and holds gear 44 against spring fingers 22. The gear ratio between pinion 40 and gear 44, in the example given, is 12 to 1.

Spring barrel 39 and the parts connected thereto are normally prevented from being rotated by spring 38 by reason of a catch 45 projecting from the spring barrel, and a stop plate 46 against which catch 45 normally rests. Catch 45 is pivoted to the spring barrel and may be rotated clockwise on this pivot so as to be released from the stop plate. The catch is biased to holding position by a light spring 41, but may be moved from this position off of stop plate 46 by a pin 49 extending laterally from the spring winding gear 36.

Thus, the action of this timing mechanism is for the motor 3| to slowly wind the spring 33 with the spring barrel held stationary during a 24 hour period. During the latter portion of this period finger 49 slowly moves catch 45 off plate 46, releasing barrel 39, which quickly makes a complete revolution under the energy stored in the spring and stops again in the position shown.

During a revolution of barrel 3!, retarding device 43 prevents too sudden starting and racing, pinion 40 rotates gear 44, of a revolution in a counterclockwise direction, and this motion is transmittedthrough clutch fingers 22 to the rotary parts connected thereto to turn them towards a zero credit and switch opening position exactly the same distance which they were advanced by one operation of credit relay I4. In this returning operation by the timing device there is no slipping of clutch 2244, since the motion of 44 is relatively slow and cam 2| and the parts connected are free to rotate, except for the small friction encountered by reason of arm 24 rubbing on the surface of cam 2|. However, when relay operates to advance the cam and connected parts, clutch 2244 slips, for the reason that the motion is sudden, the gear ratio between 44 and 40 is such as to rotate shaft 31 at a very high speed it the clutch did not slip, and furthermore such movement, if it existed, would be such as to wind spring 33. Consequently, when relay I4 operates to advance the cam 2|, clutch 2244 slips and no motion is transmitted beyond it towards the timing mechanism. But when the timing mechanism releases spring barrel 39, clutch 2244 does not slip, and this motion is positively transmitted in the opposite direction. Thus, the conditions are such that there is a one-way driving connection between the timing mechanism and credit relay mechanism which is always in engagement and in which there is no lost motion. The resetting operation is, therefore, positive and accurate. Since the energy required for this resetting operation is gradually taken from the timing motor over its entire operating period, the load imposed on the motor is negligible, and a very small motor operating under substantially constant load conditions can satisfactorily perform this service with absolute timing accuracy and a very small consumption of electric energy.

The parts are shown in the positions they will be in after the timing mechanism has returned the credit mechanism to a zero credit position and opened switch contacts 25, opening the circuit to appliance 30 and to timing motor 3|. Under these conditions it will be desirable to have spring 33 initially wound to a limited extent. If, now, a coin of the proper denomination be inserted in the top of the coin chute, it will strike lever II, turn it about its pivot I2, and close contacts I3. This movement of lever II releases the coin, which drops down into a suitable receptacle provided therefor but not shown. The contacts I3 open again and additional coins may be inserted one after the other. The closure of contacts I3 energizes credit relay I4, which actuates operating pawl I5, registering its operation on totalizing register I6, and rotating ratchet wheel |'I, of a revolution in a clockwise direction. Switch contacts 25 are closed, making available service to appliance 30 and energizing timing motor 3|, which immediately starts. Dial 20 has been turned to indicate I. During the unit timing period energy is gradually stored in spring 38 and release pin 49 slowly rotates in a clockwise direction and approaches catch 45. During the latter portion of the timing period, pin 49 moves against catch 45 and gradually moves it to the left until it slips off the stop plate.

Spring barrel 39, shaft 31, gear 40 retarded by the fan 43 now make a complete revolution in a very short interval of time not exceeding a few seconds and come to rest again with catch against plate 46. In the meantime, gear 44 makes of a revolution in a counter-clockwise direction, rotating the credit parts accordingly and returning them to their zero credit position, opening switch 25. The operation for a plurality of coins is the same, except that cam 2| is advanced proportionately further and switch 25 is not opened until a corresponding number of unit time intervals have elapsed.

By employing a self -starting synchronous motor as the timing element, the timing function is suspended in case the power fails, and consequently no loss of credit is encountered by reason of such failure. In other words, the time measured by the timing device is the time paid for when service is available.

The device is entirely automatic and requires no setting or winding operation. Coins up to the maximum credit condition may be inserted at any time without interfering with the timing cycle. The device is simple and rugged in construction and requires a minimum of electric energy for its operation.

In case additional coins are inadvertently inserted at a time when the time credit mechanism has reached the limit its capacity (11 coins in this instance), the device will, nevertheless, register the additional coins on the totalizing register IS without injury to the device and without interference with its normal operation.

.What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A coin-operated time switch comprising a credit relay, a coin chute, means responsive to the deposit of a coin in said chute for momentarily energizing said credit relay, a service switch, a movable crediting means actuated in one direction in response to the operation of said relay for closing said switch, timing means for actuating said crediting means in the opposite direction and opening said service switch a predetermined interval of time after it is closed, the crediting means being arranged to extend such time interval in response to deposit of additional coins and the repeated operation of said relay at any given time in proportion to the number of additional coins thus deposited up to a given maximum corresponding to the full capacity of said crediting means, a register operated by said credit relay for indicating the total number of coins deposited, and means allowing the credit relay to operate said register without further influencing said crediting means when the latter has reached its full capacity position.

2. A coin-controlled time switch comprising a rotary cam, a service switch controlled by said cam, the cam having an initial position where the switch is open and a plurality of other positions where the switch is closed, coin-controlled actuating means for rotating said cam in a given direction from its initial position a predetermined distance for each actuation, a constant speed timing motor, a spring which is constantly wound by said timing motor when the latter is in operation, means operated by said spring for returning said cam in the opposite direction towards its initial position, means for normally holding said returning means from operating, and time controlled means for periodically releasing said holding means. allowing said spring to unwind to move said cam the aforesaid predetermined distance for each releasing operation.

3. A coin-controlled time switch comprising a service switch, a rotary member. a coin-controlled ratchet relay for rotating said member in one direction to close said switch, timing means for mechanically rotating said member in the oppo site direction to open said switch, and a friction clutch between said timing means and rotary member, the relation of the parts and adjustment of the clutch being such as to permit slipping of the clutch only when the rotary member is moved by the ratchet relay.

4. A coin-controlled time switch comprising a circuit controlling credit cam, a coin-controlled relay for rotating said cam in one direction in steps of predetermined amount, timing means comprising a timing motor, a spring wound by the timing motor, and means controlled by the timing motor for periodically releasing said spring for periodically returning said cam toward its initial position by like amounts, and a friction clutch between said cam and turning means, the rela-.

tion of the parts being such as to permit the clutch to slip only when the cam is rotated by the credit relay.

-.romANn. arm. 

